Classic TB303 Acid




 * The 1v/Oct pitch cv is fed into a vc slew to give the portamento 'sliding' note sound. This is switched on and off by applying a cv to the slew on/off cv input. Use of a cv at the cv time socket allows slew time to be varied for larger pitch jumps.


 * The slew signal is also fed into a resonant low pass filter along with an envelope controlled by the note on/off gate signal. this, along with the noticeable attack and decay times on this envelope give the classic 'squelchy' sound to the filter shape.


 * A second envelope fed by the same gate signal shapes the note, dictated mostly by the length of note from the sequencer, just enough decay to add some interest (use of linear vca input keeps the sound more 'tight' and 'sequenced' sounding, rather than 'natural' or 'organic')


 * the distortion can be applied to give the overdriven screaming acid sound as opposed to the squelchy clean acid.